This invention relates to a can bodymaker having improved ram support and drive wherein a horizontally reciprocal ram having a forward end portion moving forwardly and rearwardly through a die assembly carrying a metal can blank forwardly therewith for performing can forming operations, and which ram was formerly supported and maintained aligned in its reciprocations between a moving rearward end connected drive mechanism and a more forwardly stationary bearing sleeve, is uniquely now isolated for such support and alignment between two, more centrally located, both stationary bearing sleeves. Thus, this unique ram isolation relegates the formerly ram supporting drive mechanism to the primary function of merely transmitting drive to the ram. The overall result is that the ram is much more simply, but with improved operating efficiency, supported and maintained aligned by the non-moving bearing sleeves while eliminating certain massive drive mechanism moving components formerly required for their supporting function and the speed of the ram strokes may be appreciably increased, if desired, while using the equivalent or less driving power, resulting in a faster and more efficiently operating overall can bodymaker.
Various forms of metal can bodymakers have heretofore been provided and that which is most closely analagous to the can bodymaker containing the improvements of the present invention includes a horizontally reciprocal ram which is movably supported in its reciprocal strokes by or between a ram rearward end connected drive mechanism constantly moving with the ram and a more forwardly positioned bearing sleeve secured stationary on the bodymaker. More specifically, various gears, crank arms, drive arms and rods of the bodymaker transform rotative motion into horizontally reciprocal or horizontally forward and rearward motion within the bodymaker drive mechanism, the drive mechanism motion finally culminating in a relatively massive, horizontally forwardly and rearwardly moving hydrostatic oil bearing slide. The rearward end of the ram is supported on and driven forwardly and rearwardly by this hydrostatic oil bearing slide with, as previously stated, the forward point of support for the ram being a bearing sleeve, particularly a hydrostatic oil bearing sleeve, secured stationary on the bodymaker and receiving, supporting and guiding the ram moving therethrough. A forward end portion of the ram receives a shallow metal cup blank thereover at a location forwardly of the bearing sleeve and when the ram is at the rearward end of and is just commencing its forward stroke, with the ram in continuing forward movement carrying the cup blank forwardly through a die assembly to form the cup blank into a relatively deep, cup-shaped can body, overall generally in the usual manner of can bodymakers.
Thus, in this prior bodymaker, the ultimately forward terminus of the bodymaker drive mechanism which is the hydrostatic oil bearing slide must not only move with and provide driving motion to the rearward end of the ram in all positions of the ram, but must also fully support and fully maintain alignment of the ram with both the more forward bearing sleeve and the even further more forward die assembly. Obviously, the only two points of support for the ram and that required to maintain the ram in alignment with the die assembly in all positions of the ram are the slide at the rearward end and the sleeve forwardly thereof, the constantly moving slide required to move with the ram progressively decreasing the distance between it and the bearing sleeve during forward motion of the ram and movably increasing such distance during rearward movement of the ram. Due to this complex requirement of drive transmission, ram rearward end full support and maintaining of alignment over constantly changing distances relative to the bearing sleeve, the slide must necessarily be relatively massive with complex moving support on the bodymaker extending over a relatively large stabilizing distance in the direction of ram projection. Furthermore, the slide for the optimum possible results in this relatively complex arrangement has made use of a relatively large number of hydrostatic oil bearing pads at various locations between it and its supporting bodymaker, again increasing complexity.
In overall result, although the described prior complex bodymaker ram movable support has produced satisfactory operating characteristics within even quite impressive speed limitations, even better operating characteristics are now desirable and even higher operating speeds required. Furthermore, it is desirable to greatly reduce the complexity of this ram support despite the requirement for attainment of higher speeds in order to reduce the cost of original bodymaker fabrication, as well as the cost of original and continuing assembly and maintenance for maintaining the necessary ram constantly closely aligned movements. For these reasons, an improved ram support and alignment concept is required which will surmount the above discussed limitations of the prior construction while meeting the described increased results.